| 摘要 |
<p>1,148,364. Polysilicic acid-organic polymer complexes and compositions. E. I. DU PONT DE NEMOURS & CO. 6 July, 1967 [8 July, 1966], No. 31272/67. Headings C3P and C3T. [Also in Division H1] A polymeric material comprises a cured complex of 40-95% by weight of polysilicic acid and the balance to 100% of a preformed OH-containing organic polymer having less than one OH group per chain carbon atom. Examples of polymers are polyvinyl alcohol, propional, or butyral, partially hydrolysed polyvinyl acetate or vinyl ester/ethylene copolymer, and copolymers of tetrafluoroethylene, vinyl fluoride, vinylidene fluoride, or chlorotrifluoroethylene with hydroxy-ethyl, propyl, butyl, or hexyl vinyl ethers or with vinyl acetate hydrolysed after polymerization. The polysilicic acid is the hydrolysis product of a silicic acid ester, e.g. ethyl silicate. The components are mixed in solution in alcohols and optionally dioxane or acetic acid and as surfactant a block copolymer of mixed 2-4 C alkylene oxides with dimethyl siloxane. The solvents are then evaporated and the coating cured at R.T.-160‹ C. Polymers used in the examples are polyvinyl propional, alcoholysed vinyl acetate-tetrafluoroethylene copolymer and 4-hydroxybutyl vinyl ether-tetrafluoroethylene copolymer.</p> |
